Function Data Attributes

Function Data Attributes (sorted by subject)

Abscissa

The abscissa values are the x values in the (x,y) data points of the function. If the function is unevenly spaced (see AbscissaSpacing), then the abscissa values are stored as a column vector in the function. The abscissa values must be real. If the function is evenly spaced, the abscissa values are not actually stored, but are determined by the AbscissaMin and AbscissaInc. The Abscissa data type is stored in AbscissaDataType.

If you set the abscissa with a vector, the abscissa of each of the functions in the imat_fn will be set to that vector.

AbscissaAxisLab

This is a character string of maximum length 20 that can be used to override the default abscissa axis label. It will appear in place of the default axis label when the function is graphed in I-deas.

AbscissaDataType

Defines the data type for the abscissa. It is always assumed to be a real quantity. The available data types and their corresponding numeric identifier are shown in the table below. The attribute specified determines how the data is converted when it is stored and retrieved by I-deas.

Numeric Identifier	Data Type
0	'Unknown'
1	'General'
2	'Stress'
3	'Strain'
5	'Temperature'
6	'Heat Flux'
8	'Displacement'
9	'Force'
11	'Velocity'
12	'Acceleration'
13	'Excitation Force'
15	'Pressure'
16	'Mass'
17	'Time'
18	'Frequency'
19	'RPM'
20	'Order'
21	'Sound Pressure'
22	'Sound Intensity'
23	'Sound Power'
24	'Cycles'
25	'Torque'
26	'Moment'
27	'LoadFactor'
28	'Gravitational Acceleration'
29	'Element Force'
30	'Element Moment'
31	'Signal'
32	'Unitless Scalar'
33	'Unitless Real'
34	'Unitless Integer'
35	'Voltage'
36	'Electric Current'

These same data attributes may be assigned to the Ordinate and Z-Axis as well. The "Unknown" data type assumes unitless data. The "General" data type lets you define your own units to the data using the Abscissa Exponents.

AbscissaExpForce

An integer value which defines the force exponent for the abscissa data type. This needs to be set explicitly only for the "General" AbscissaDataType. For all others, it is defined automatically. If this attribute is changed, the AbscissaDataType will be set to "General". During importing and exporting, the exponents are used for unit conversion.

AbscissaExpLength

An integer value which defines the length exponents for the abscissa data type. This needs to be set explicitly only for the "General" AbscissaDataType. For all others, it is defined automatically. If this attribute is changed, the AbscissaDataType will be set to "General". If AbscissaTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used for unit conversion.

AbscissaExpTemp

An integer value which defines the temperature exponents for the abscissa data type. This applies needs to be set explicitly only for the "General" AbscissaDataType. For all others, it is defined automatically. If this attribute is changed, the AbscissaDataType will be set to "General". The standard abscissa data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used for unit conversion.

AbscissaExpTime

An integer value which defines the time exponents for the abscissa data type. This attribute is not used for any units conversion. Note that there is no place to store this attribute in a Universal file or ADF, so any changes made to this attribute will be lost in a round-trip through these file formats.

AbscissaInc

If AbscissaSpacing is even, this stores the spacing, or increment, of the abscissa values. If AbscissaSpacing is uneven, this stores the maximum abscissa value of the function.

AbscissaMin

This stores the minimum abscissa value. If the AbscissaSpacing is even, all other abscissa values are calculated from this minimum using AbscissaInc. You cannot modify the minimum abscissa value of unevenly spaced data.

AbscissaOffset

OBSOLETE and not available.

AbscissaSpacing

Defines the abscissa spacing as even or uneven. If the spacing is defined as even, the Abscissa is not stored, but is generated as necessary from AbscissaMin and AbscissaInc. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Uneven'
1	'Even'

AbscissaTypeQual

This attribute affects the interpretation of the units exponents. This attribute is necessary for all abscissa data types except for "General". The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Translation'
1	'Rotation'
2	'Translation Squared'
3	'Rotation Squared'

The difference in interpretation of the units exponent is in the length. For rotation, the length is unitless and assumed to be in radians.

AbscissaUnitsLab

This is a character string of maximum length 20 that can be used to override the default abscissa units label. It will appear in place of the default abscissa units label when the function is graphed in I-deas.

AmplitudeUnits

This attribute, together with Normalization, defines the amplitude units for spectral data. The available data types and their corresponding numeric identifier are shown in the table below.

A linear spectrum computed with half-peak units (and 'Units squared' Normalization) will have an amplitude of 0.5 when analyzing a unit sine wave. A spectrum computed with peak units will have unit amplitude when analyzing a unit sine wave. A spectrum computed with RMS units will have an amplitude of sqrt(0.5) when analyzing a unit sine wave.

CoordSys

OBSOLETE and not available.

CreateDate

Lists the date that the function was created. It is automatically stored when the function is created. While it can be modified in MATLAB, it will be overwritten when written to an ADF. It is stored as a character string of length 20, in the format "DD-MMM-YY HH:MM:SS".

ExpDampingFact

Defines the damping factor used as the decay rate of an exponential window that has been applied to a time history. If the damping factor is known, the damping values calculated from parameter estimation during a modal analysis can be corrected to their true values.

FunctionType

Defines the type of data stored in the function. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'General or Unknown'
1	'Time Response'
2	'Auto Spectrum'
3	'Cross Spectrum'
4	'Frequency Response Function'
5	'Transmissibility'
6	'Coherence'
7	'Auto Correlation'
8	'Cross Correlation'
9	'Power Spectral Density (PSD)'
10	'Energy Spectral Density (ESD)'
11	'Probability Density Function'
12	'Spectrum'
13	'Cumulative Frequency Distribution'
14	'Peaks Valley'
15	'Stress/Cycles'
16	'Strain/Cycles'
17	'Orbit'
18	'Mode Indicator Function'
19	'Force Pattern'
20	'Partial Power'
21	'Partial Coherence'
22	'Eigenvalue'
23	'Eigenvector'
24	'Shock Response Spectrum'
25	'Finite Impulse Response Filter'
26	'Multiple Coherence'
27	'Order Function'
28	'Phase Compensation'
29	'Harmonic Function'
30	'Octave'
31	'Temperature'
32	'Stress vs Strain'
33	'Life'
34	'Campbell Diagram'

In I-DEAS, some operations may be restricted to certain function types. For example, only functions of type "Time Response", "Peaks Valley", and "Finite Impulse Response Filter" may be exported to an ATI file.

IDLine1

This is also called the function Title, used for descriptive text. It is limited to 80 characters. When a function is plotted in I-DEAS, the IDLine1 appears on the legend by default. If a function was created by measurement in I-DEAS Test, then the IDLine1 will be taken from the label of the response channel in the channel table.

IDLine2

The second function descriptor line, used for descriptive text. It is limited to 80 characters. If a function was created by measurement in I-DEAS Test, then the IDLine2 will be taken from the label of the reference channel in the channel table.

IDLine3

The third function descriptor line, used for descriptive text. It is limited to 80 characters.

IDLine4

The fourth function descriptor line, used for descriptive text. It is limited to 80 characters. When a function is plotted in I-DEAS, the IDLine4 appears on the legend by default. (But it is referred to as "Line 3" in the Legend management form.) If a function was created by measurement in I-DEAS Test, then the IDLine4 will be taken from the Measurement Description for that run.

IRIGTime

The IRIG is a time stamp that can be used to associate a global time value with a particular record. Practically speaking, this can be used to synchronize datasets acquired using different hardware in a lab, or keep an accurate record of when a measurement was made. The IRIG Time format is of the form 'AAA:HH:MM:SS.SSSSSS', where AAA is the number of days from the start of the year (with January 1 being day 1).

LoadCase

OBSOLETE and not available.

MaxOrdValImag

OBSOLETE and not available.

MaxOrdValReal

OBSOLETE and not available.

MeasurementRun

Integer value which specifies the run number of the measurement. It is used by I-DEAS Test to indicate groups of data acquired at the same time. It is automatically assigned during measurement so that it is a unique number for the ADF.

MinOrdValImag

OBSOLETE and not available.

MinOrdValReal

OBSOLETE and not available.

ModifyDate

Lists the date that the function was last modified. It is automatically updated when the function is modified. While this attribute can be modified in MATLAB, it will be overwritten when written to an ADF. It is stored as a character string of length 20, in the format "DD-MMM-YY HH:MM:SS".

Normalization

This attribute, together with AmplitudeUnits, is set by I-DEAS Test during data acquisition to document the normalization method used to define a spectrum. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Unknown'
1	'Units squared'
2	'Units squared/Hz'
3	'Units squared sec/Hz'

The normalization is important for properly computing the RMS of a spectrum. The names are most meaningful for an "Auto Spectrum" FunctionType. For this type of function, if the normalization is "Units squared", then the sum of the spectral values should match the mean square of the time response. If the normalization is "Units squared/Hz", then the sum of the spectral values times the frequency increment should match the mean square of the time response. If the normalization is "Units squared sec/Hz", then the sum of the spectral values times the square of the frequency increment should match the mean square of the time response.

For linear spectra, these characteristics are true of the modulus squared of the spectrum.

NumberElements

Integer value which defines the number values in the function. It is the same as the number of Abscissa and Ordinate values in the function.

OctaveAvgType

Integer value which defines the type of response averaging applied to octave results. This attribute is meaningful only for the Octave function type.

Numeric Identifier	Octave Average Type
0	'None'
1	'Fast'
2	'Slow'
3	'Impulse'
4	'Linear'

The octave average type is stored as an integer.

OctaveFormat

This attribute sets the octave format that was used to define a spectrum. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	None
1	Octave
3	One third octave (1/3)
n	1/n octave

The octave format is stored as an integer.

OctaveOverallRMS

OBSOLETE and not available.

OctaveWeightedRMS

OBSOLETE and not available.

OrdDenDataType

Defines the data type for the ordinate denominator. The available data types and their corresponding numeric identifier are shown in the table under AbscissaDataType. The attribute specified determines how the data is converted when it is stored and retrieved by I-DEAS.

The denominator is ordinarily a reference or an input excitation. If a reference measurement was not made, the denominator qualifiers are not used (should be set to "Unknown"). The ordinate numerator and denominator data types are stored separately to accommodate functions such as frequency response functions.

OrdDenExpForce

An integer value which defines the force exponents for the ordinate denominator data type. This needs to be set explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". During importing and exporting, the exponents are used for unit conversion.

OrdDenExpLength

An integer value which defines the length exponents for the ordinate denominator data type. This needs to be set explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". If OrdDenTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used for unit conversion.

OrdDenExpTemp

An integer value which defines the temperature exponents for the ordinate denominator data type. This needs to be set explicitly only for the "General" OrdDenDataType. For all others, it is defined automatically. If this attribute is changed, the OrdDenDataType will be set to "General". The standard ordinate data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used for unit conversion.

OrdDenExpTime

An integer value which defines the time exponents for the ordinate denominator data type. This attribute is not used for any units conversion. Note that there is no place to store this attribute in a Universal file or ADF, so any changes made to this attribute will be lost in a round-trip through these file formats.

OrdDenTypeQual

This attribute affects the interpretation of the ordinate denominator units exponents. This attribute is necessary for all OrdDenDataTypes except for "General". The available data types and their corresponding I-DEAS numeric identifier are shown in the table under AbscissaTypeQual.

OrdNumDataType

Defines the data type for the ordinate numerator. The available data types and their corresponding numeric identifier are shown in the table under AbscissaDataType. The attribute specified determines how the data is converted when it is stored and retrieved by I-DEAS.

The numerator is ordinarily the response to an input excitation. If a reference measurement was not made, the ordinate data should be stored in the numerator. The ordinate numerator and denominator data types are handled separately to accommodate functions such as frequency response functions.

OrdNumExpForce

An integer value which defines the force exponents for the ordinate numerator data type. This needs to be set explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". During importing and exporting, the exponents are used for unit conversion.

OrdNumExpLength

An integer value which defines the length exponents for the ordinate numerator data type. This needs to be set explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". If OrdNumTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used for unit conversion.

OrdNumExpTemp

An integer value which defines the temperature exponents for the ordinate numerator data type. This needs to be set explicitly only for the "General" OrdNumDataType. For all others, it is defined automatically. If this attribute is changed, the OrdNumDataType will be set to "General". The standard ordinate data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used for unit conversion.

OrdNumExpTime

An integer value which defines the time exponents for the ordinate numerator data type. This attribute is not used for any units conversion. Note that there is no place to store this attribute in a Universal file or ADF, so any changes made to this attribute will be lost in a round-trip through these file formats.

OrdNumTypeQual

This attribute affects the interpretation of the ordinate numerator units exponents. This attribute is necessary for all OrdNumDataTypes except for "General". The available data types and their corresponding I-DEAS numeric identifier are shown in the table under AbscissaTypeQual.

OrdOffsetImag

OBSOLETE and not available.

OrdOffsetReal

OBSOLETE and not available.

OrdScaleImag

OBSOLETE and not available.

OrdScaleReal

OBSOLETE and not available.

Ordinate

The ordinate values are the y values in the (x,y) data points of the function. The ordinate values are stored as a column vector of either real or complex numbers. OrdinateType specifies the type of data stored.

If you set the ordinate with a vector, the ordinate of each of the functions in the imat_fn will be set to that vector.

OrdinateAxisLab

This is a character string of maximum length 20 that can be used to override the default Ordinate axis label. It will appear in place of the default axis label when the function is graphed in I-DEAS.

OrdinateType

This attribute determines the ordinate value storage. This attribute is set automatically based on the characteristics of the ordinate. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
2	'Real Single' [precision]
4	'Real Double' [precision]
5	'Complex Single' [precision]
6	'Complex Double' [precision]

(Although I-DEAS stores data in single precision, all data is stored in MATLAB in double precision.)

OrdinateUnitsLab

This is a character string of maximum length 20 that can be used to override the default Ordinate units label. It will appear in place of the default units label when the function is graphed in I-DEAS.

OwnerName

Character string of length 16 which identifies the username of the person who created the function.

PulsesPerRev

Specifies the number of pulses per revolution or pulses per cycle for a tachometer measurement. If SamplingType is "RPM from Tach" or "Frequency from Tach", this attribute indicates the number of pulses per revolution or cycle that were used to compute the RPM or frequency.

ReferenceCoord

Character string of up to 14 characters which defines the reference coordinate of the function. It is a combination of ReferenceNode and ReferenceDir. Note that setting the ReferenceCoord also sets the ReferenceNode and ReferenceDir, and vice versa.

The reference coordinate normally refers to the physical orientation of the exciter on a tested structure. This information is made up of a location number, direction, and sense. For example, a reference coordinate of '1X+' indicates a location of point number 1 on the structure, with a positive direction along the X axis.

ReferenceDir

String of up to 4 characters which identifies the direction and sense of the reference. Any four characters may be used, but physical meaning is attached to the directions 'X+', 'X-', 'Y+', 'Y-', 'Z+', 'Z-', 'RX+', 'RX-', 'RY+', 'RY-', 'RZ+', and 'RZ-'. ReferenceNode, combined with ReferenceDir, make up ReferenceCoord.

ReferenceEntity

OBSOLETE and not available.

ReferenceNode

Integer value which specifies the node number of the reference. Enter a zero if you do not want a value to appear in the attributes. ReferenceNode, combined with ReferenceDir, make up ReferenceCoord.

ResponseCoord

Character string of up to 14 characters which defines the response coordinate of the function. It is a combination of ResponseNode and ResponseDir. Note that setting the ResponseCoord also sets the ResponseNode and ResponseDir, and vice versa.

The response coordinate normally refers to the physical orientation of a measured response to an input to the structure. This information is made up of a location number, direction, and sense. For example, a response coordinate of '2X+' indicates a location of point number 2 on the structure, with a positive direction along the X axis.

ResponseDir

String of up to 4 characters which identifies the direction and sense of the response. Any four characters may be used, but physical meaning is attached to the directions 'X+', 'X-', 'Y+', 'Y-', 'Z+', 'Z-', 'RX+', 'RX-', 'RY+', 'RY-', 'RZ+', and 'RZ-'. ResponseNode, combined with ResponseDir, make up ResponseCoord.

ResponseEntity

OBSOLETE and not available.

ResponseNode

Integer value which specifies the node number of the response. Enter a zero if you do not want a value to appear in the attributes. ResponseNode, combined with ResponseDir, make up ResponseCoord.

SamplingType

This attribute documents the sampling type that was used during a data measurement. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'Dynamic'
1	'Static'
2	'RPM From Tach'
3	'Frequency From Tach'

Sampling types other than "Dynamic" apply to data obtained during Transient Measurements and Order Tracking.

SetRecord

Integer value specifying the set number the function is associated with. Single records are specified with a SetRecord of 0. When exported, all functions with a given nonzero SetRecord are stored in a Function Set, which can be plotted in I-DEAS with XYZ plotting. When exporting to an existing ADF, if Function Sets already exist in the ADF, SetRecord will specify the offset from the highest set number already written to the ADF.

UserValue1

Specifies a real value of significance to the user. This attribute could be used to store a value that does not fall under any of the other attributes.

UserValue2

Specifies a real value of significance to the user. This attribute could be used to store a value that does not fall under any of the other attributes.

UserValue3

Specifies a real value of significance to the user. This attribute could be used to store a value that does not fall under any of the other attributes.

UserValue4

Specifies a real value of significance to the user. This attribute could be used to store a value that does not fall under any of the other attributes.

Version

Integer value which specifies the function's version number. When exporting to an ADF, the combination of ReferenceCoord, ResponseCoord, and Version must be unique. No such requirement is imposed in MATLAB. If a record with the same combination already exists in the ADF, the version number will be incremented until a unique combination is achieved.

WeightingType

This attribute specifies the weighting function that was applied to generate an acoustic spectrum. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'None' (or Unknown)
1	'A weighting'
2	'B weighting'
3	'C weighting'
4	'D weighting'

WindowType

This attribute documents the type of window that was applied to the data when it was processed. The available data types and their corresponding numeric identifier are shown in the table below.

Numeric Identifier	Data Type
0	'None'
1	'Hanning Narrow'
2	'Hanning Broad'
3	'Flattop'
4	'Exponential'
5	'Impact'
6	'Impact and Exponential'

ZAxisDataType

Defines the data type for the ZGeneralValue associated with this function. Z-axis values are used in Function Sets to position functions on an XYZ plot. The available data types and their corresponding I-DEAS numeric identifier are shown in the table under AbscissaDataType. The attribute specified determines how the data is converted when it is stored and retrieved by I-DEAS.

ZAxisExpForce

An integer value which defines the force exponents for the ZGeneralValue associated with this function. This needs to be specified explicitly only for the "General" ZAxisDataType. For all others, it is defined automatically. If this attribute is changed, the ZAxisDataType will be set to "General". During importing and exporting, the exponents are used for unit conversion.

ZAxisExpLength

An integer value which defines the length exponents for the ZGeneralValue associated with this function. This needs to be specified explicitly only for the "General" ZAxisDataType. For all others, it is defined automatically. If this attribute is changed, the ZAxisDataType will be set to "General". If ZAxisTypeQual is set to rotation, the length is assumed to be unitless and expressed in radians. During importing and exporting, the exponents are used for unit conversion.

ZAxisExpTemp

An integer value which defines the temperature exponents for the ZGeneralValue associated with this function. This needs to be specified explicitly only for the "General" ZAxisDataType. For all others, it is defined automatically. If this attribute is changed, the ZAxisDataType will be set to "General". The standard ordinate data types use the Kelvin or Rankine scale to express temperature. During importing and exporting, the exponents are used for unit conversion.

ZAxisExpTime

An integer value which defines the time exponents for the Z axis data type. This attribute is not used for any units conversion. Note that there is no place to store this attribute in a Universal file or ADF, so any changes made to this attribute will be lost in a round-trip through these file formats.

ZAxisTypeQual

This attribute affects the interpretation of the Z axis units exponents for the ZGeneralValue associated with this function. This attribute is necessary for all ZAxisDataTypes except for "General". The available data types and their corresponding I-DEAS numeric identifier are shown in the table under AbscissaTypeQual.

ZGeneralValue

Specifies a real number for the Z axis value associated with this function (usually a member of a function set). This is used when plotting XYZ or waterfall plots to define the Z axis of the plot.

ZOrderValue

Specifies a real number for the order value associated with this function (usually a member of a function set). This is used when plotting XYZ or waterfall plots to define the Z axis of the plot when the Z axis is of data type Order.

ZRPMValue

Specifies a real number for the RPM value associated with this function (usually a member of a function set). This is used when plotting XYZ or waterfall plots to define the Z axis of the plot when the Z axis is of data type RPM.

ZTimeValue

Specifies a real number for the time value associated with this function (usually a member of a function set). This is used when plotting XYZ or waterfall plots to define the Z axis of the plot when the Z axis is of data type Time.

Function Data Attributes